146 Entomological Papers. [No. 2. 



rather abruptly narrowed and slightly truncated at the apex ; these 

 characteristics more distinctly expressed in the labial ones. All 

 the lower part of the mouth is situated in or forms a cavity. Tho- 

 rax a little broader tlran the bead nearly twice as broad as it is 

 long, quadratic at the base, slightly narrowed towards the apex, 

 ant. angles slightly produced, the ant. margin can hardly be called 

 emarginated, 2 slight sinuosities at the base, firmly applied to the 

 elytra and as broad as these. Scutellum broad, triangular. Tho 

 elytra rather abruptly cut away at the apex, internal angles rather 

 obtuse, slightly dehiscent. Legs stout and strongly armed, very 

 mueb in the- manner of my Cyelosomus Dyticoides, of which the 

 insect under consideration in various respects reminds me most 

 forcibly. The spinea of the tibiae are inserted on ridges, the ant., 

 ones being dilated. The tarsi are all concave on the inner side. 

 I have been unable to discover anything in them by which to dis- 

 tinguish the sexes, not even additional spines or bristles. How- 

 ever, the sexes appear well marked by the difference in size. The 

 ant. tarsi are dilated, the intermed. and post, ones more and more 

 elongated and the joints subcylindric ; joint 1 of the latter is longer 

 than the 3 following together, all 4 have the edges of tbeir concave 

 inner side serrated — an extraoi dinary circumstance. The highly 

 developed prosternum reminds me again of Cyclosoinus. 



The habits of these insects are those of the Amaras ; they live 

 in dry, sandy places under grass and leaves ; at certain times they 

 take freely to their wings and O. arenaria may then be caught in 

 great numbers at night about the light. This species is very com- 

 mon in all the dry and sandy parts of the neighbourhood of 

 Colombo; the pretty little O. Oerstaekeri, however, is scarce. 



49. Oosoma arenaria. W, 



O. supra brunneo-genea, subtus magis minusve brunnea, pedibus, 

 palpis antennarumque basi testaceis, tarsis, labro limboque angus- 

 tissimo obscurioribus ; capite ad clypei margiuem post, punctis 2- 

 impresso ; thorace ad basin obsoletissime 4-foveolato, linea longi- 

 tud. abbreviata, indistincta, diviso, basi anticeque obsoletissime 

 striguloso ;. subtus tenuiter hirsuta ; long. corp. 2^ — 3 lin.,- lat. 1J — 

 U lin. 



